Вадим Губий

$item_prices_db = $db->query("SELECT `market_hash_name`, `price` FROM `items` WHERE `market_hash_name` IN(?list)", [$marketnames], 'assoc');

$ipdb = [];

foreach ($item_prices_db as $ipd) {
	$ipdb[$ipd['market_hash_name']] = [$ipd['price']];
}

foreach ($item_array as &$v) {
	$v['price'] = $ipdb[$v['market_hash_name']][0];
}

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